This reference element is called a key.
theme
The legend identifies the colors that represent the bars.
legend
The legend identifies patterns used for each series.
The legend is the function that identifies the data marker for each series in a chart.
legend
It is called the "key".
A legend or key.
Name box
Legend.
Tip text, identifying the series, the point and the value of the data, or the name of an element, such as an axis or the wall of the chart.
legend
Legend